This reminds me your note:
https://tango.0pointer.de/pipermail/pulseaudio-discuss/2009-July/004519.html
PA does not make use of hardware mixing. And I don't plan to change
that. It's obsolete technology. CPUs these days come with extensions
such as MMX or SSE precisely for speeding up DSP tasks such as PCM
mixing. This is way more flexible that hw mixing, and definitely the
way to the future, both on the desktop and on embedded envs as well.
The "obsolete technology" -- who made this decision? Is it your private
opinion or any suggestion from sound card manufacturers?
It seems that HW companies still produce the "obsolete technology".

Quite agreed [says a former kernel audio driver maintainer], and I will
go even farther:

Maybe since the times you worked on audio drivers the design of the
sound cards changed a little and stuff like SSE became largely available?

I am well-versed in modern audio hardware -- moreso than you, apparently.
Jeff